In plastic forming, a resin is flowed and stuck to the abutting faces of the metal molds, thus forming flashes. Most of these flashes are removed together with a formed product when such product is taken out from the molds. However, if there remain any flashes on the mold faces, such residual flashes will provoke the occurrence of further flashes or other troubles. It is therefore necessary to completely remove flashes from the mold faces by cleaning the mold faces upon the completion of each forming process.
In particular, when a thermo-setting resin of the epoxy type is used, its stickiness to the mold faces is strong. It becomes therefore very difficult to manually remove the flashes. Furthermore, if the molds are pressed with any residual flashes stuck thereto, there is produced an extremely great partial pressure which provokes damages to the abutting faces of the molds.
In order to eliminate the dangers associated with a manual flash removal and to improve the flash removing efficiency, there has been developed a cleaning method according to which air is blown to the mold faces. The flashes stuck to the mold faces are then removed by rotary brush means, and the thus removed flashes are sucked away. According to such cleaning method, however, since the rotary brush means are used as flash removing members, the removing action of such brush means is made merely to such extent as to sweep off the flashes by the brush tip portions. Accordingly, effective flash removal cannot be expected even though a cooling action by blowing air is combined with a sweeping action by the rotary brushes. It therefore still takes a relatively long period of time to completely remove the flashes. Thus, such method can hardly contribute to improvements in efficiency of manufacturing plastic forming products.